Method and apparatus for allocating resources and processing confirmation information

ABSTRACT

A method and an apparatus for allocating ACKnowledgement (ACK)/Non-ACKnowledgement (NACK) channel resources and processing confirmation information are disclosed. The method includes: The network side determines one physical channel area among multiple physical channel areas to be used by an ACK/NACK channel, and notifies the determined physical channel area to a User Equipment (UE) so as to enable the UE to determine a channel for receiving or sending ACK/NACK information in the determined physical channel area according to a mapping rule. Moreover, the network side may send or receive ACK/NACK information on the physical channel area that includes the ACK/NACK channel. The method and apparatus improve the utilization ratio and flexibility of the ACK/NACK channel, and reduce the probability of conflict generated by the ACK/NACK channel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/253,722, filed on Jan. 22, 2019, which is a continuation of U.S.patent application Ser. No. 15/702,459, filed on Sep. 12, 2017 (now U.S.Pat. No. 10,211,962), which is a continuation of U.S. patent applicationSer. No. 15/130,678, filed on Apr. 15, 2016 (now U.S. Pat. No.9,768,937), which is a continuation of U.S. patent application Ser. No.14/951,059, filed on Nov. 24, 2015 (now U.S. Pat. No. 9,345,005), whichis a continuation of U.S. patent application Ser. No. 13/145,984, filedon Jul. 22, 2011 (now U.S. Pat. No. 9,219,580), which is a NationalStage of International Patent Application No. PCT/CN2010/070352, filedon Jan. 25, 2010, which claims priority to Chinese Patent ApplicationNo. 200910105293.9, filed on Jan. 24, 2009, and Chinese PatentApplication No. 200910130084.X, filed on Apr. 14, 2009. All of theafore-mentioned patent applications are hereby incorporated by referencein their entireties.

TECHNICAL FIELD

The present disclosure relates to communications technologies, and inparticular, to a technology of allocating resources and processingconfirmation information.

BACKGROUND

In a communication system, carrier aggregation is applied to supportwider bandwidth and accomplish the peak value rate. In the carrieraggregation technology, multiple branch carriers are aggregated tosupport wideband transmission. Every branch carrier isbackward-compatible. Depending on capabilities of a User Equipment (UE),the UE can receive or send signals of multiple carriers simultaneously.

The communication between the UE and the Base Station (BS) is generallybased on a Hybrid Automatic Repeat Request (HARQ) technology in theprocess of sending/receiving data of each branch carrier. That is, thedata of a transmission block is code-modulated and sent; after thereceiver receives the data, if the data passes the Cyclical RedundancyCheck (CRC), the receiver regards the decoding as correct and returns anACKnowledgement (ACK) message; if the data fails the CRC, the receiverregards the decoding as incorrect, and returns a Non-ACKnowledgement(NACK) message. The ACK message and the NACK message are collectivelyknown as confirmation messages, and the transmitter performs furtheroperations such as HARQ according to the received confirmation message.

In the sending or receiving of the data of multiple carriers, anindependent HARQ process of each carrier is applied. For example, datamay be sent over a physical shared channel, and control information maybe sent over a physical control channel. Physical Downlink ControlChannel (PDCCH) is made up of Control Channel Elements (CCEs). Aphysical control channel is generally made up of 1, 2, 4, or 8 CCEs.When multiple carriers exist, each carrier has an independent HARQprocess so that confirmation information may need to be sent by multiplePhysical Uplink Control Channels (PUCCHs).

In the case of a single carrier, the resources for the uplink carrier tofeed back the ACK/NACK are reserved according to the maximum number ofCCEs on the corresponding downlink carrier.

In the case that the carrier aggregation scheme is aggregation of pairedcarriers, namely, the number of uplink carriers is equal to the numberof downlink carriers, the single-carrier rule is still applicable toreserving and mapping of the ACK/NACK channel resources. However, in thecase that the carrier aggregation scheme is aggregation of pairedcarriers, especially aggregation of UE-specific non-paired carriers, thesingle-carrier rule is no longer applicable to reserving and mapping ofthe ACK/NACK channel resources. Because the corresponding feedbackchannel is uncertain, it is impossible to feed back the ACK/NACKmessages corresponding to non-paired downlink carriers or uplinkcarriers.

SUMMARY

The embodiments of the present disclosure provide a method and anapparatus for allocating resources and processing confirmationinformation to determine locations of sending or receiving ACK/NACKchannels.

A method for allocating ACK/NACK channel resources includes:

determining one physical channel area among multiple physical channelareas to be used by an ACK/NACK channel, and notifying the determinedphysical channel area to a UE through signaling so as to enable the UEto determine a channel for receiving or sending ACK/NACK information inthe determined physical channel area according to a mapping rule.

An apparatus for allocating ACK/NACK channel resources includes:

a physical channel area determining module, configured to determine onephysical channel area among multiple physical channel areas to be usedby an ACK/NACK channel; and

a notifying module, configured to notify the determined physical channelarea to a UE through signaling so that the UE can determine a channelfor receiving or sending ACK/NACK information in the determined physicalchannel area according to a mapping rule.

A method for processing confirmation information includes:

obtaining a physical channel area indication which indicates a physicalchannel area that includes an ACK/NACK channel among multiple physicalchannel areas; and

sending or receiving ACK/NACK information in the physical channel areathat includes the ACK/NACK channel according to the physical channelarea indication.

An apparatus for processing confirmation information includes:

a physical channel area obtaining module, configured to obtain aphysical channel area indication which indicates a physical channel areathat includes an ACK/NACK channel among multiple physical channel areas;and

a confirmation information processing module, configured to send orreceive ACK/NACK messages on the physical channel area that includes theACK/NACK channel according to the physical channel area indicationobtained by the physical channel area obtaining module.

In the embodiments of the present disclosure, one physical channel areais determined in multiple physical channel areas, and the location ofthe ACK/NACK channel is determined on this physical channel areaaccording to the mapping rule. In this way, the ACK/NACK channels can bescheduled flexibly, and therefore the ACK/NACK corresponding tonon-paired uplink carriers or non-paired downlink carriers can be fedback.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solution under the present disclosure moreclearly, the following describes the accompanying drawings involved inthe embodiments of the present disclosure. Apparently, the accompanyingdrawings described below are not exhaustive, and persons of ordinaryskill in the art can derive other drawings from such accompanyingdrawings without any creative effort.

FIG. 1 shows how to determine carriers in an embodiment of the presentdisclosure;

FIG. 2 shows a process of allocating ACK/NACK channel resources in anembodiment of the present disclosure;

FIG. 3 shows a process of processing confirmation information in anembodiment of the present disclosure;

FIG. 4 shows an LTE-specific area in an embodiment of the presentdisclosure;

FIG. 5 shows an LTE-specific area and an LTE area in an embodiment ofthe present disclosure;

FIG. 6 is a first schematic diagram of an application instance in anembodiment of the present disclosure;

FIG. 7 is a second schematic diagram of an application instance in anembodiment of the present disclosure;

FIG. 8 shows a scenario of crossed ACK/NACK mapping in an embodiment ofthe present disclosure;

FIG. 9 shows a scenario of non-crossed ACK/NACK mapping in an embodimentof the present disclosure;

FIG. 10 is a third schematic diagram of an application instance in anembodiment of the present disclosure;

FIG. 11 shows an apparatus for allocating ACK/NACK channel resources inan embodiment of the present disclosure;

FIG. 12 shows an apparatus for processing confirmation information in aUE in an embodiment of the present disclosure;

FIG. 13 shows an apparatus for processing confirmation information on anetwork side in an embodiment of the present disclosure; and

FIG. 14 shows a structure of a BS provided in an embodiment of thepresent disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following detailed description is provided in conjunction with theaccompanying drawings to provide a thorough understanding of the presentdisclosure. Evidently, the drawings and the detailed description aremerely representative of particular embodiments of the presentdisclosure rather than all embodiments. All other embodiments, which canbe derived by those skilled in the art from the embodiments providedherein without any creative effort, shall fall within the protectionscope of the present disclosure.

To make the technical solution, objectives and merits of the presentdisclosure clearer, the following describes the embodiments of thepresent disclosure in more detail with reference to the accompanyingdrawings.

Non-paired uplink carriers or non-paired downlink carriers have nocorresponding paired carriers for feeding back ACK/NACK messages.Therefore, resources may be added into the paired carriers to enablefeedback of confirmation information of non-paired carriers. Forexample, as shown in FIG. 1, a User 1 uses downlink carrier 1, downlinkcarrier 2, and uplink carrier 1. Uplink carrier 1 is paired withdownlink carrier 1, and the corresponding resource may be added onuplink carrier 1 as a feedback area of downlink carrier 2 (non-paireddownlink carrier). That is, the paired downlink carrier feeds backinformation in the legacy feedback area of the corresponding uplinkcarrier, and the non-paired downlink carrier feeds back information in anewly added area of the paired uplink carrier. For non-paired uplinkcarriers, the foregoing method serves as a reference.

The foregoing method enables feedback of ACK/NACK messages of non-paireduplink carriers or non-paired downlink carriers. However, because thefeedback area is fixed, if many resources are unused in the legacyfeedback area, resource waste may occur, and it is impossible toschedule ACK/NACK resources flexibly.

In this embodiment and the following embodiments, the confirmationinformation indicates whether a receiver receives transmission contentfrom a transmitter correctly. For ease of description, ACK indicatesthat the content is received correctly, and NACK indicates that thecontent is received incorrectly. ACK and NACK are only examples ofconfirmation messages. In practice, other confirmation messages may beapplied instead. The corresponding confirmation information channelresource is a resource for transmitting confirmation messages. In thefollowing embodiments, the ACK/NACK channel resource is taken as anexample of a resource of the corresponding confirmation informationchannel.

In the channel resource allocation scheme provided in this embodiment,one physical channel area may be determined among multiple physicalchannel areas to be used by the ACK/NACK channel on the network side,and then information about the determined physical channel area isnotified to the UE by signaling. In this way, the UE can determine thechannel for sending or receiving ACK/NACK information in a correspondingphysical channel area according to a mapping rule, and the ACK/NACKinformation can be sent or received on the physical channel of thephysical channel area.

For example, the corresponding physical channel area may be a legacyarea or current area. The legacy area is designed for feeding backconfirmation information in a legacy system, and the current area isdesigned for feeding back confirmation information in a current systemcompatible with the legacy system. Specifically, the legacy area and thecurrent area may respectively be LTE areas and LTE-A-specific areas; orthe legacy area and the current area may respectively be CoordinatedMulti-Point (CoMP) areas and non-CoMP areas, where the CoMP areas areused by CoMP users exclusively for sending ACK/NACK information, and theACK/NACK information sent in the CoMP area may be modulated through thesequences specific to CoMP users; or, the legacy area and the currentarea may respectively be non-relay areas and relay areas, where therelay areas are used by relay stations for receiving and sendingACK/NACK ; or, the legacy area and the current area may be categorizedinto other physical channel areas. Each area may further include one ormore subareas. For example, an LTE-A-specific area may include one ormore LTE-A-specific subareas.

In this embodiment, multiple physical channel areas do not overlap atall, or overlap partly. For example, the legacy area may be orthogonalto the current area (namely, without overlap), or may overlap with thecurrent area.

In this embodiment, more than one physical channel area needs to beconfigured or divided on the network side. At least one of the physicalchannel areas is designed for feeding back confirmation information ofpaired carriers, and at least one of the physical channel areas isdesigned for feeding back confirmation information of non-pairedcarriers. In the foregoing description, a legacy area is taken as anexample of the at least one physical channel area for feeding backconfirmation information of paired carriers, and a current area is takenas an example of the at least one physical channel area for feeding backconfirmation information of non-paired carriers. In the followingembodiments, for ease of description, a physical channel area forfeeding back confirmation information of paired carriers is called afirst physical channel area; and a physical channel area for feedingback confirmation information of non-paired carriers is called a secondphysical channel area.

The LTE-A-specific areas may further include ACK/NACK channelscorresponding to CCEs in the public search space in the LTE system,namely, the first 16 ACK/NACK channels of the ACK/NACK channel resourcesof the LTE, so as to improve utilization ratio of an ACK/NACK channel.The foregoing physical channel areas may be placed on one or morecarriers, and a physical channel area may be set on one carrier ormultiple carriers. In the following embodiments, the setting of thephysical channel areas is the same and therefore not described again.

The following provides more details about the process of allocatingACK/NACK channel resources in an embodiment of the present disclosure.As shown in FIG. 2, the process may include:

Step 21: A network side (such as a BS) determines a physical channelarea among multiple physical channel areas to be used by an ACK/NACKchannel.

The determined physical channel area may be an uplink physical channelarea to be used by an uplink ACK/NACK channel, or a downlink physicalchannel area to be used by a downlink ACK/NACK channel. That is, thisstep is applicable to both an uplink scenario and a downlink scenario.

In the process of selecting a physical channel area in multiple physicalchannel areas, taking the LTE system and LTE-A system as an example, theselection may include: When the channel redundancy of the LTE area isgreat, for example, the PDCCH has a high CCE level or low load on thepaired downlink carriers, and the ACK/NACK mapping of the pairedcarriers of the current user does not conflict, it is determined thatthe current user uses the LTE area for ACK/NACK channel mapping, and theuser is notified through signaling; when the channel redundancy of theLTE area is small, for example, the PDCCH has a low CCE level or highload on the paired downlink carriers, and the ACK/NACK mapping of thenon-paired carriers of the current user does not conflict, it isdetermined that the current user uses the LTE-A-specific area forACK/NACK channel mapping, and the user is notified through signaling;when the ACK/NACK mapping of the LTE area conflicts with the ACK/NACKmapping of the LTE-A-specific area of the non-paired carriers of theuser, the scheduling for the current user is disabled.

Step 22: Notify the determined physical channel area to a UE throughsignaling.

Specifically, the physical channel area that includes the ACK/NACKchannel may be notified to the UE dynamically through bits or ascrambling code. That is: one or more bits are used to indicate thephysical channel area in which the user side receives or sends ACK/NACKinformation, and the one or more bits are sent to the UE throughsignaling. For example, in a Physical Downlink Control Channel, one bitrepresents two states (corresponding to two different physical channelarea identifiers); and two bits represent four states (corresponding tofour different physical channel area identifiers). In this way, thephysical channel area of the ACK/NACK channel is notified to a userdynamically. After receiving the one bit or two bits, the user side cansend or receive ACK/NACK information on the ACK/NACK channel included inthe physical channel area corresponding to the one bit or two bits; ordifferent scrambling codes are used to indicate the physical channelarea in which the user side receives or sends ACK/NACK information, andthe scrambling codes are sent to the UE through signaling.

In the foregoing processing, if one or more bits are used to indicatethe physical channel area in which the user side receives or sendsACK/NACK information, new bits may be added into the PDCCH to indicatethe physical channel area in which the user side receives or sends theACK/NACK information; or all or part of the states represented by theexisting bits in the PDCCH may be multiplexed to indicate the physicalchannel area in which the user side receives or sends ACK/NACKinformation. For example, three bits in the PDCCH represent an HARQprocess, and all or part of the eight states represented by the threebits may be used to indicate the physical channel area in which the userside receives and sends ACK/NACK information.

Alternatively, the signaling for determining the physical channel areamay be encoded together with other signaling in the physical controlchannel such as PDCCH.

For example, the signaling for determining the physical channel area maybe encoded together with the ACK/NACK indication bits in the PDCCH. TheACK/NACK indication bit indicates the occupied ACK/NACK channel inphysical control channels. For example, eight ACK/NACK channels areconfigured in a physical channel area, and an ACK/NACK indication withat least three bits may be used to indicate the ACK/NACK channeloccupied by a user. New bits may be added in the physical controlchannel as ACK/NACK indication bits, or other bits in the physicalcontrol channel may be multiplexed as ACK/NACK indication bits. Forexample, the resource allocation granularity is increased so that thebits of the resource allocation field in the PDCCH are multiplexed asACK/NACK indication bits. The physical channel area may be the firstphysical channel area, or, preferably, the second physical channel area.

One or more states represented by the ACK/NACK indication bits may beused to indicate the determined physical channel area to a UE. Forexample, when there are three ACK/NACK indication bits, 000 indicatesthat the determined physical channel area is the first physical channelarea, and 001-111 indicate the 7 ACK/NACK channels in the secondphysical channel area respectively.

Specially, if many users, such as more than 8 users, are scheduled onthe non-paired carriers simultaneously and confirmation informationneeds to be fed back, the ACK/NACK channels in the second physicalchannel area may be insufficient. In this case, the ACK/NACK indicationbits may be encoded together with the signaling for determining thephysical channel area, namely, one or more states of the ACK/NACKindication bits are used to indicate the determined physical channelarea. In addition, the first physical channel area may employ animplicit mapping rule of CCE index. In this case, one or more statesrepresented by the ACK/NACK indication bits are used to notify thecurrent user, and a ACK/NACK channel of the user is mapped to the firstphysical channel area according to the implicit mapping rule of PDCCHCCE index.

In the case that the signaling for determining the physical channel areais multiplexed together with other signaling in the physical controlchannel, another instance is: the signaling for determining the physicalchannel area is encoded together with carrier indication bits. Thecarrier indication bits indicate the carrier scheduled by the currentphysical control channel. For example, in the case of four PDSCHcarriers, at least two bits in the PDCCH need to be used as carrierindication bits to indicate which one of the four carriers is currentlyscheduled for the PDCCH.

If the carrier indication includes three bits and four PDSCH carriersexist currently, one bit or two states are redundant. In this case, theredundant bit or redundant states of the carrier indication bits may beused to indicate the determined physical channel area. In this scenario,both the first physical channel area and the second physical channelarea may employ the implicit mapping rule of CCE index; or, the firstphysical channel area employs the implicit mapping rule of CCE index,and the second physical channel area uses the ACK/NACK indication bitsto indicate the specific ACK/NACK channel; or, the first physicalchannel area uses the implicit mapping rule of CCE index, and the secondphysical channel area may be configured exclusively for the userindicated by the cross-carrier PDCCH through high-layer semi-staticsignaling.

The signaling for determining the physical channel area is encodedtogether with other signaling in the physical control channel, and theexisting fields in the physical control channel may be used to indicatethe determined physical channel area to a UE, which reduces conflict ofthe ACK/NACK channel, improves flexibility of scheduling and savessignaling overhead.

In embodiments of this disclosure, in the detailed process of notifyinga UE, layer-1 signaling/layer-2 signaling (L1/L2 signaling) or RadioResource Control (RRC) signaling may be used to send a correspondingnotification. In this way, the determined physical channel area isnotified to the UE.

In embodiments of this disclosure, the network may use RRC signaling tosend the start offset information. The start offset informationindicates the start position of the physical channel area for receivingor sending ACK/NACK information, for example, the start position of theLTE area, or the start position of the LTE-specific area (including thestart position of an LTE-A-specific subarea). The start offsetinformation is used for dividing physical channel areas. Therefore, thestart offset information is not sent any more after being sentinitially, or is sent at long regular intervals, or sent at longirregular intervals. The step of notifying the start offset informationto the UE through RRC signaling may be performed before, during or afterthe foregoing step. After the foregoing step is performed, the step ofsending the start offset information is not necessarily performed.Accordingly, the mapping rule may be: the start offset information iscombined with the sequence number of the CCE to indicate the channel(namely, ACK/NACK channel) used by a specific user side to receive orsend ACK/NACK information. Further, in the case that an LTE-A-specificarea includes multiple LTE-A-specific subareas, the LTE-A-specificsubareas may overlap partly or completely with one another, and aLTE-A-specific subarea may overlap with a LTE area of the LTE systempartly or completely. Specifically, the corresponding start offsetinformation may be applied so that multiple areas (LTE areas orLTE-A-specific subareas) overlap partly or completely.

In this embodiment, the configuring or allocation of physical channelareas may be performed once or repeatedly on the network side; and maybe performed periodically or irregularly. After configuring orallocating the physical channel area, the network side needs to notify aUE, and the notification method is described above. Alternately, if boththe network side and a UE know the allocation of the physical channelarea, it is not necessary to notify the UE through signaling, and thephysical channel area known to the network side and the UE is applied.

Through the ACK/NACK channel resource allocation solution above, thenetwork side can feed back ACK/NACK information corresponding tonon-paired uplink carriers or non-paired downlink carriers, and canindicate the physical channel area that includes the ACK/NACK channel tothe UE flexibly, which improves utilization ratio of the ACK/NACKchannel resources and reduces overhead and possible conflicts. Throughconfiguring or allocation of the physical channel area, the resourcesare utilized more efficiently and flexibly.

A method for processing confirmation information (namely, ACK/NACKinformation) is provided in an embodiment of the present disclosure.This method is implemented in a UE or a network side, as detailed below.

(I) Processing confirmation information in a UE

In a UE, the process of processing confirmation information may include:obtaining a physical channel area indication which indicates thephysical channel area that includes the ACK/NACK channel in multiplephysical channel areas; and the UE sends or receives ACK/NACKinformation on the physical channel area that includes the ACK/NACKchannel according to the physical channel area indication.

The corresponding multiple physical channel areas are described above.

The following provides more details about the process of processingconfirmation information in a UE in an embodiment of the presentdisclosure. As shown in FIG. 3, the process may include:

Step 31: Obtain a physical channel area indication.

In the process of receiving the physical channel area indication sent bythe network side, a UE may use (but without being limited to using) oneor more bits in the PDCCH to obtain the physical channel area indicationfor receiving or sending ACK/NACK information; or, the UE may use ascrambling code in the PDCCH to obtain the physical channel areaindication for receiving or sending ACK/NACK information; or, the UE mayuse other high-layer signaling (such as RRC signaling) to receive andobtain the corresponding physical channel area indication information.

Step 32: Determine the channel used for sending or receiving ACK/NACKinformation.

Specifically, the channel used for sending or receiving ACK/NACKinformation is determined in the physical channel area indicated by thephysical channel area indication according to a predefined mapping rule.That is, the ACK/NACK channel used in the UE for receiving or sendingACK/NACK information is determined according to the predefined mappingrule among multiple ACK/NACK channels included in the physical channelarea used by the UE for receiving or sending ACK/NACK information, andtherefore, the UE can determine the specific channel for receiving orsending ACK/NACK information in the physical channel area. The mappingrule is a principle of selecting a channel for sending or receivingACK/NACK information in the physical channel area. For example, themapping rule may be: The start offset information is combined with theCCE sequence number to indicate the channel used by the UE for receivingor sending ACK/NACK information. For example, a user 1 uses uplinkcarrier 1, downlink carrier 1, and downlink carrier 2; the start offsetinformation is 16; the CCE sequence numbers that need to be fed back ondownlink carrier 2 are 20, 21, 22, and 23; the minimum CCE sequencenumber is combined with the start offset information, and therefore, theACK/NACK channel numbered 36(20+16) in the corresponding physicalchannel area is selected for feedback.

Further, the channel used for receiving or sending ACK/NACK messages inmultiple channels included in the different LTE-A-specific subareas orLTE areas according to different mapping rules.

In this embodiment, the mapping rule further includes: using theACK/NACK channel indicated by the ACK/NACK indication bits.

Step 33: Send or receive the corresponding ACK/NACK information throughthe channel determined for sending or receiving ACK/NACK information.

In the foregoing process of processing confirmation information, the UEcan know the channel used for sending or receiving ACK/NACK information,and receive or send ACK/NACK information accordingly. In this way, theACK/NACK information corresponding to non-paired uplink carriers ornon-paired downlink carriers can be fed back, and the ACK/NACK channelscan be scheduled flexibly.

(II) Process of processing confirmation information in the network side

In the network side, the process of processing confirmation informationmay include: The network side obtains locally a physical channel areaindication information which indicates the physical channel area thatincludes the ACK/NACK channel in multiple physical channel areas; andthe network side sends or receives ACK/NACK information on the physicalchannel area that includes the ACK/NACK channel according to thephysical channel area indication information. The process of processingconfirmation information in the network side may be implemented in aBase Station, namely, the Base Station obtains locally a physicalchannel area indication information for receiving or sending ACK/NACKinformation, and sends or receives the corresponding ACK/NACKinformation according to the physical channel area indicationinformation.

While the network side sends or receives ACK/NACK information in thephysical channel area that includes the ACK/NACK channel, the networkside may perform the following operation additionally: determining thechannel in the physical channel area used for receiving or sendingACK/NACK information. Specifically, the network side may determine thechannel used for receiving or sending ACK/NACK information in multiplechannels included in different LTE-A-specific subareas or LTE areasaccording to different mapping rules. The mapping rule is a principle ofselecting a channel for sending or receiving ACK/NACK information in aphysical channel area.

In the foregoing process of processing confirmation information, thenetwork side can determine the channel used for sending or receivingACK/NACK information, and send or receive ACK/NACK informationaccordingly.

This embodiment may include the following step additionally: A UEobtains the locations of the first physical channel area and the secondphysical channel area allocated by the network side. This step may beimplemented by receiving start offset information. The UE may know thestart point of each physical channel area in the multiple physicalchannel areas according to the start offset information, and determinethe location of each physical channel area.

To facilitate the understanding of the embodiments of the disclosure,the following provides details about the implementation process of theembodiments of the present disclosure with reference to the accompanyingdrawings, assuming that the embodiments are applied in an LTE system andan LTE-A system.

Embodiment 1

The first embodiment deals with how the network side allocates ACK/NACKchannel resources and receives or sends ACK/NACK information, and how aUE receives or sends ACK/NACK information.

(I) The network side allocates ACK/NACK channel resources and receivesor sends ACK/NACK information

(1) Multiple physical channel areas are configured in the network side.

In the detailed implementation process, a certain number ofLTE-A-specific areas (which may include multiple LTE-A-specificsubareas) may be introduced in order to reduce performance loss causedby ACK/NACK interference between cells and prevent increase of too muchACK/NACK resource overhead. The number of LTE-A-specific areasintroduced may be configured through high-layer signaling.

As shown in FIG. 4, the number of ACK/NACK channels in the LTE area is N(namely, ACK/NACK channels numbered from 0 to N−1). In the N channels,the first 16 ACK/NACK channels are numbered from 0 to 15, and the 16ACK/NACK channels are the ACK/NACK channels corresponding to the CCE inthe public search space. The number of ACK/NACK channels in theLTE-A-specific area is M. The LTE-A-specific area may include the first16 ACK/NACK channels (numbered from 0 to 15) corresponding to the CCE ofthe public search space in the LTE area. For the users mapped to theACK/NACK area of the LTE, the 16 ACK/NACK channels are numbered from 0to 15; for the users mapped to the LTE-A-specific area, the 16 ACK/NACKchannels are numbered from N+M−16 to N+M−1, which ensures that thenumber of ACK/NACK channels of the LTE-A-specific area is M.

(2) The physical channel areas for sending ACK/NACK information areallocated. Specifically, the physical channel areas for sending ACK/NACKinformation are allocated to the network side, and the physical channelareas for sending ACK/NACK information are allocated to a UE.

As shown in FIG. 4, in the process of allocating physical channel areas,the ACK/NACK channel corresponding to non-paired downlink carriers maybe mapped to the configured LTE-A-specific area (which includes multipleLTE-A-specific subareas); and the ACK/NACK channel corresponding topaired downlink carriers is still mapped to the physical channel area(LTE area) reserved by the LTE system for sending or receiving ACK/NACKinformation according to the rule of the LTE system.

Further, in the case that the ACK/NACK channel corresponding tonon-paired downlink carriers is mapped to the LTE-A-specific area, thecorresponding start offset information may be introduced. As shown inFIG. 5, the start offset information divides the correspondingLTE-A-specific area into multiple LTE-A-specific subareas. EachLTE-A-specific subarea corresponds to each non-paired downlink carrierrespectively, and the configuration of different start offsetinformation makes multiple LTE-A-specific subareas not overlapped atall, or overlapped completely (all start offsets are the same), oroverlapped partly. For example, the corresponding start offsetinformation makes the ACK/NACK channel corresponding to the downlinkcarrier fall within the LTE area reserved by the LTE system or withinthe LTE-A-specific area. If the ACK/NACK channel falls within the LTEarea reserved by the LTE system, the redundant ACK/NACK channel in theLTE area can be utilized efficiently, and the resources reserved in theLTE-A-specific area can be reduced.

(3) The network side sends ACK/NACK information in the allocatedphysical channel area, and notifies a UE of the physical channel areaallocated to the UE and the network side for sending ACK/NACK messages.Meanwhile, the network side receives the ACK/NACK information sent by aUE in the physical channel area which is allocated to the UE for sendingACK/NACK information.

When the network side notifies a UE of the physical channel areaallocated to the UE and the network side for sending ACK/NACKinformation, one bit in the PDCCH may indicate different physicalchannel areas, namely, indicate that the area mapped to the ACK/NACKchannel is the LTE area or LTE-A-specific area. Through this bit, the UEdetermines the physical channel area that includes the uplink ordownlink ACK/NACK channel, and determines the physical channel area thatincludes the ACK/NACK channel used for receiving or sending ACK/NACKinformation.

As shown in FIG. 6, assuming that the UE has three downlink carriers andone uplink carrier, the mapping rule for mapping of the ACK/NACK channelof the downlink carriers (paired downlink carriers) corresponding to theuplink carriers is the same as the mapping rule of the LTE system. Forthe mapping relations between the PDCCH and the ACK/NACK of other twodownlink carriers (namely, non-paired downlink carriers), thecorresponding ACK/NACK channel may be determined according to themapping of the start offset information and the CCE sequence number ofthe PDCCH on the corresponding downlink carrier. The start offsetinformation indicates that the physical channel area covering theACK/NACK channel is an LTE area or an LTE-A-specific subarea; and theCCE sequence number indicates the location of the ACK/NACK channel inthe corresponding LTE area or LTE-A-specific subarea. In addition, inthe LTE-A-specific area, other mapping rules may be applied to determinethe corresponding ACK/NACK channel.

Further, still assuming that 1 bit is added into the PDCCH (1 bitindicates two states: state 0 and state 1), as shown in FIG. 7, theACK/NACK channel mapping process may include:

(a) For the mapping of the ACK/NACK channel resources on the paireddownlink carrier (CC0), the mapping rule of the LTE system may beapplied, namely, ACK/NACK channel sequence number corresponds to theminimum CCE index of the PDCCH.

(b) For the mapping of the ACK/NACK channel resources on the non-paireddownlink carriers (CC1 and CC2), a new mapping rule may be introduced,which is indicated by 1 bit in the PDCCH on the local carrier, asdetailed below:

When the PDCCH on the non-paired downlink carrier is composed of 1 CCE,the ACK/NACK channel corresponds to the CCE index of the PDCCH of thisdownlink carrier;

When the PDCCH on the non-paired downlink carrier is composed of 2 CCEs,1 bit in the PDCCH may indicate the positions of two ACK/NACK channels,and the ACK/NACK channels correspond to the CCE indices of the PDCCH ofthis downlink carrier, respectively;

When the PDCCH on the non-paired downlink carrier is composed of 4 CCEs,1 bit in the PDCCH may indicate the positions of two ACK/NACK channels,and the ACK/NACK channels are mapped to the second CCE index and thefourth CCE index among four CCEs, which reduces the probability ofconflicting with the ACK/NACK channel resource in the paired carriers;and

When the PDCCH on the non-paired downlink carrier is composed of 8 CCEs,the mapping rule is the same as the scenario of 4 CCEs above. In thiscase, the ACK/NACK channels are mapped to two CCE indices selected,which are any two CCE indices in the second, fourth, sixth, and eighthCCE indices in the 8 CCEs.

It should be noted that: This embodiment is applicable to determiningthe uplink ACK/NACK channel, and applicable to dynamic indication of thedownlink ACK/NACK channel. For example, 1 specific bit in the PDCCH maybe used to indicate the specific mapping area of the downlink ACK/NACKchannel so that the corresponding downlink ACK/NACK channel can bedetermined. The detailed process is similar to the foregoing process.

Further, when the network side notifies a UE of the physical channelarea allocated to the UE and the network for sending ACK/NACKinformation, multiple bits in the PDCCH may dynamically indicate thephysical channel areas that include the ACK/NACK channels. For example,two bits in the PDCCH dynamically indicate the physical channel areasthat include four ACK/NACK channels.

In addition, when the network notifies the UE of the physical channelarea allocated to the UE and the network side for sending ACK/NACKinformation, if start offset information is configured, the start offsetinformation may be notified to the UE through an RRC signaling. Forexample, the corresponding start offset information is broadcast on thecorresponding downlink carrier; or, all start offset information isbroadcast on the paired carriers, and may be carried on the signalingthat carries the reserved ACK/NACK channel resource specific to LTE-A;or, the start offset information is carried on the PDCCH, and theexisting bit field represents the start offset information, for example,HARQ process, and Modulation Coding Scheme (MCS) etc.

(II) UE receives or sends ACK/NACK information

A UE receives an indication of the physical channel area that is sent bythe network side, and receives or sends the ACK/NACK messages accordingto the indication.

Specifically, a UE receives the indication sent by the network side.According to the indication, the UE determines the physical channel areaallocated by the network side to the UE and the network side for sendingACK/NACK information. Then, the UE can determine the ACK/NACK channelavailable to the UE in the corresponding physical channel area forsending ACK/NACK information according to a mapping rule, and receiveand or send ACK/NACK information through the ACK/NACK channel.

Embodiment 2

The method of dynamically notifying the area mapped to the ACK/NACKchannel in the first embodiment above may be extended so that the methodis applicable to send ACK/NACK information in a CoMP system. Thecorresponding physical channel areas in the CoMP system include CoMPareas and non-CoMP areas. As shown in FIG. 8, a CoMP area is applicableto a scenario of crossed ACK/NACK mapping, and applicable to a scenarioof non-crossed ACK/NACK mapping as shown in FIG. 9. That is, in theACK/NACK mapping of paired downlink carriers, non-CoMP areas or CoMPareas may be selected dynamically.

After the method applied to the CoMP system, as regards how the networkside allocates ACK/NACK channel resources and receives or sends ACK/NACKinformation, and how a UE receives or sends ACK/NACK information, theprocesses are similar to those described in the first embodiment above,and therefore are not described again.

Embodiment 3

The third embodiment deals with a scenario of ACK/NACK channelindication among multiple subframes. That is, the third embodimentaccomplishes flexible indication of ACK/NACK channels among multiplesubframes, and overcomes conflict.

Specifically, assuming there are 3 downlink carriers and 1 uplinkcarrier; the PDCCH may include 1 bit which indicates the ACK/NACKchannels between two subframes.

For example, as shown in FIG. 10, all PDCCHs of a UE (in FIG. 10, it isassumed there are 3 PDCCHs) are carried on a downlink carrier (such asdownlink main carrier). The data of the current subframe may be in thesubframe of the PDCCH, but the data of other carriers indicated and thecorresponding PDCCH need to be deferred for one subframe, which is shownby the arrow in downlink carrier 1 and downlink carrier 2 in FIG. 10;and the uplink ACK/NACK messages are fed back on the 4th subframe afterthe corresponding data channel.

In the foregoing process, the PDCCHs of the same UE are transmitted onthe same subframe, but the uplink ACK/NACK channel feeds backinformation on different subframes. Consequently, the ACK/NACKcorresponding to the PDCCH of the next subframe may conflict.

To overcome the conflict, an LTE-A-specific area may be reserved on theuplink subframe. Through the indication mode in the processing solutionprovided herein (for example, indication mode described in the firstembodiment), the positions of the ACK/NACK channels are notified to theUE. That is, the positions of the ACK/NACK channels in the LTE area orLTE-A-specific area are indicated.

In the embodiments of the present disclosure, because LTE-A-specificarea is introduced, the ACK/NACK information corresponding to thenon-paired uplink carriers or non-paired downlink carriers can be fedback, a tradeoff is achieved between the ACK/NACK resource reservationoverhead and ACK/NACK resource mapping conflict, and the ACK/NACKperformance loss caused by interference between cells is reduced.Meanwhile, start offset information is introduced so that the ACK/NACKchannel resources can be scheduled more flexibly. For example, when theControl Format Indication (CFI) value of the paired downlink carriers issmall, the start offset information may make the physical channel areafall within the LTE area. In this way, the redundant ACK/NACK channel inthe LTE area can be utilized efficiently, the resources reserved in theLTE-A-specific area can be reduced, and the utilization ratio of theACK/NACK channel is improved. In the embodiments of the presentdisclosure, the LTE-A-specific area includes the ACK/NACK channelcorresponding to the CCE in the public search space, which furtherimproves the utilization ratio of the ACK/NACK channel. In theembodiments of the present disclosure, an LTE-A-specific area (orLTE-A-specific subarea) can be reserved for each non-paired downlinkcarrier of a user respectively to reduce conflict of the ACK/NACKchannel. In the embodiments of the present disclosure, throughallocation of different physical channel areas, the ACK/NACK resourcescan be dynamically released for the sake of transmitting data. Forexample, when there are few users of LTE, or when the LTE area hasconsiderable redundancy, the ACK/NACK channel can be mapped to the LTEarea through dynamic adjustment. In this case, the reservedLTE-A-specific area resources can be released and become available todata channel transmission.

Persons of ordinary skill in the art should understand that all or partof the steps of the method provided in the embodiments above may beimplemented by a program instructing relevant hardware. The program maybe stored in computer readable storage media. When the program runs, thesteps of the method specified in any embodiment above are executed. Thestorage media may be a magnetic disk, CD-ROM, Read-Only Memory (ROM), orRandom Access Memory (RAM).

An apparatus for allocating channel resources is provided in anembodiment of the present disclosure. The apparatus may be configured onthe network side, for example, in a Base Station. As shown in FIG. 11,the apparatus may include:

a physical channel area determining module 901, configured to determineone physical channel area among multiple physical channel areas to beused by an ACK/NACK channel, namely, select a physical channel area tobe used by an ACK/NACK channel among multiple physical channel areas,where the physical channel area may be an uplink physical channel areaor downlink physical channel area; and a notifying module 902,configured to notify a UE of the physical channel area determined by thephysical channel area determining module 901 so that the UE candetermine the channel available for receiving or sending ACK/NACKinformation in the physical channel area according to a predefinedmapping rule, where the detailed notification method may be but is notlimited to: notifying the UE of the corresponding physical channel areathrough L1/L2 signaling or RRC signaling.

The physical channel areas in the physical channel area information sentby the notifying module 902 may include LTE areas and LTE-A-specificareas. The LTE-A-specific areas may include multiple LTE-A-specificsubareas, and the LTE-A-specific areas may include the ACK/NACK channelscorresponding to the CCE of the public search space in the LTE system;or, the physical channel areas may include COMP areas and non-COMPareas.

The notification method of the notifying module 902 may be but is notlimited to: One or more bits in the PDCCH indicates the physical channelarea in which the UE receives or sends ACK/NACK messages; or, differentscrambling codes loaded on the PDCCH indicate the physical channel areain which the UE receives or sends ACK/NACK messages.

In this apparatus, the notifying module 902 may be configured to sendstart offset information to the UE through an RRC signaling. Thecorresponding start offset information may be configured to determinethe start point of a physical channel area. According to a predefinedmapping rule, the start offset information may be combined with a CCEsequence number to indicate the channel used by the UE for receiving orsending ACK/NACK information among multiple channels included in thephysical channel area in which the UE receives or sends ACK/NACKinformation.

In this embodiment, the apparatus may further include a physical channelarea allocating module, which is configured to allocate at least onefirst physical channel area and at least one second physical channelarea. The first physical channel area includes a confirmationinformation channel for sending confirmation information of pairedcarriers, and the second physical channel area includes a confirmationinformation channel for sending confirmation information of non-pairedcarriers.

An apparatus for processing confirmation information is provided in anembodiment of the present disclosure. The apparatus may be configured ina UE. As shown in FIG. 12, the apparatus may include a physical channelarea obtaining module and a confirmation information processing module.

(1) The physical channel area obtaining module 1001 is configured toobtain a physical channel area indication. The indication indicates thephysical channel area that includes a ACK/NACK channel in multiplephysical channel areas. The physical channel area may be a physicalchannel area that includes an uplink ACK/NACK channel, or a physicalchannel area that includes a downlink ACK/NACK channel. The physicalchannel area obtaining module 1001 may receive the physical channel areaindication sent by the network side through L1/L2 signaling or RRCsignaling.

The physical channel area obtaining module 1001 may obtain the physicalchannel area indication of the ACK/NACK channel through one or more bitsin the PDCCH; or obtain the physical channel area indication of theACK/NACK channel through a scrambling code in the PDCCH; or obtain thephysical channel area indication by other means.

(2) The confirmation information processing module 1002 is configured tosend or receive ACK/NACK information on the physical channel area thatincludes the ACK/NACK channel according to the physical channel areaindication obtained by the physical channel area obtaining module 1001.

The confirmation information processing module 1002 is furtherconfigured to determine a channel in the physical channel area to beused by the ACK/NACK channel, and specifically, determine the channelavailable for receiving or sending ACK/NACK information in multiplechannels included in different LTE-A-specific subareas or LTE areasaccording to different mapping rule.

In this apparatus, the corresponding physical channel areas include LTEareas and LTE-A-specific areas, or include CoMP areas and non-CoMPareas. Further, the LTE-A-specific areas include multiple LTE-A-specificsubareas, and the LTE-A-specific area may include a ACK/NACK channelcorresponding to the CCE of the public search space in the LTE system.

Another apparatus for processing confirmation information is provided inan embodiment of the present disclosure. The apparatus may be configuredon the network side, for example, set in a Base Station. As shown inFIG. 13, the apparatus may include a physical channel area obtainingmodule 1101 and a confirmation information processing module 1102.

(1) The physical channel area obtaining module 1101 is configured toobtain a physical channel area indication. The indication indicates thephysical channel area that includes a ACK/NACK channel in multiplephysical channel areas. The physical channel area may be a physicalchannel area that includes an uplink ACK/NACK channel, or a physicalchannel area that includes a downlink ACK/NACK channel. The physicalchannel area obtaining module 1101 may obtain the physical channel areaindication locally.

(2) The confirmation information processing module 1102 is configured tosend or receive ACK/NACK information on the physical channel area thatincludes the ACK/NACK channel according to the physical channel areaindication obtained by the physical channel area obtaining module 1101.

The confirmation information processing module 1102 is furtherconfigured to determine a channel in the physical channel area to beused by the ACK/NACK channel, and specifically, determine a channelavailable for receiving or sending ACK/NACK information in multiplechannels included in different LTE-A-specific subareas or LTE areasaccording to different mapping rule.

In this apparatus, the corresponding physical channel areas include LTEareas and LTE-A-specific areas, or include CoMP areas and non-CoMPareas. Further, the LTE-A-specific areas include multiple LTE-A-specificsubareas, and the LTE-A-specific area may include ACK/NACK channelscorresponding to the CCEs of the public search space in the LTE system.

A Base Station is provided in an embodiment of the present disclosure.As shown in FIG. 14, the BS may include the physical channel areadetermining module 901, notifying module 902, physical channel areaobtaining module 1101, and confirmation information processing module1102. The physical channel area obtaining module 1101 obtains thephysical channel area indication determined by the physical channel areadetermining module 901. The functions of the modules have been describedabove, and are not repeated here any further.

Through the apparatus for allocating channel resources and the apparatusfor processing confirmation information above, the ACK/NACK informationcorresponding to the non-paired uplink carrier or downlink carrier canbe fed back, the utilization ratio of a ACK/NACK channel is improved,the flexibility of scheduling ACK/NACK resources is improved, and theprobability of conflict generated by ACK/NACK channels is reduced.

The above descriptions are merely exemplary embodiments of the presentdisclosure, but not intended to limit the protection scope of thepresent disclosure. Any modifications, variations or replacement thatcan be easily derived by those skilled in the art shall fall within theprotection scope of the present disclosure. Therefore, the protectionscope of the present disclosure is subject to the appended claims.

1. A method, comprising: receiving, by a terminal device from a basestation, a physical downlink shared channel (PDSCH) on a downlinkcarrier of at least two downlink carriers, wherein the at least twodownlink carriers are capable of being configured for the terminaldevice; determining, by the terminal device, a physical uplink controlchannel (PUCCH) resource for carrying acknowledgement ornon-acknowledgement (ACK/NACK) in response to the PDSCH, wherein thePUCCH resource is dynamically located within a first PUCCH resource areaor a second PUCCH resource area; and transmitting, by the terminaldevice on the PUCCH resource, the ACK/NACK in response to the PDSCH. 2.The method according to claim 1, further comprising: receiving, by theterminal device from the base station, an indication indicating a PUCCHresource area in the first PUCCH resource area or the second PUCCHresource area; and determining, by the terminal device, the PUCCHresource area based on the indication.
 3. The method according to claim2, wherein the indication is carried on a physical downlink controlchannel (PDCCH).
 4. The method according to claim 1, wherein the firstPUCCH resource area is for feeding back ACK/NACK in a legacy system, andthe second PUCCH resource area is for feeding back confirmationinformation in a system compatible with the legacy system.
 5. The methodaccording to claim 1, wherein the first PUCCH resource area is forcarrying ACK/NACK information in a long term evolution (LTE) system, andthe second PUCCH resource area is for carrying ACK/NACK information in along term evolution advanced (LTE-A) system compatible with the LTEsystem.
 6. The method according to claim 2, further comprising:determining, by the terminal device, the PUCCH resource in thedetermined PUCCH area according to a mapping rule, wherein the mappingrule is a principle of selecting a PUCCH resource for transmittingACK/NACK information in a PUCCH resource area.
 7. The method accordingto claim 6, wherein the first PUCCH resource area and the second PUCCHresource area correspond to different mapping rules.
 8. The methodaccording to claim 7, wherein one mapping rule in the different mappingrules is that the PUCCH resource is indicated by a start offsetinformation combined with a sequence number of a control channel element(CCE).
 9. An apparatus, comprising: a storage medium includingexecutable instructions; and a processor, wherein the executableinstructions, when executed by the processor, cause the apparatus to:receive a physical downlink shared channel (PDSCH) on a downlink carrierof at least two downlink carriers, wherein the at least two downlinkcarriers are capable of being configured for the terminal device;determine a physical uplink control channel (PUCCH) resource forcarrying acknowledgement or non-acknowledgement (ACK/NACK) in responseto the PDSCH, wherein the PUCCH resource is dynamically located within afirst PUCCH resource area or a second PUCCH resource area; and transmit,on the PUCCH resource, the ACK/NACK in response to the PDSCH.
 10. Theapparatus according to claim 9, wherein the executable instructions,when executed by the processor, further cause the apparatus to: receivean indication indicating a PUCCH resource area in the first PUCCHresource area or the second PUCCH resource area; and determine the PUCCHresource area based on the indication.
 11. The apparatus according toclaim 10, wherein the indication is carried on a physical downlinkcontrol channel (PDCCH).
 12. The apparatus according to claim 9, whereinthe first PUCCH resource area is for feeding back ACK/NACK in a legacysystem, and the second PUCCH resource area is for feeding backconfirmation information in a system compatible with the legacy system.13. The apparatus according to claim 9, wherein the first PUCCH resourcearea is for carrying ACK/NACK information in a long term evolution (LTE)system, and the second PUCCH resource area is for carrying ACK/NACKinformation in a long term evolution advanced (LTE-A) system compatiblewith the LTE system.
 14. The apparatus according to claim 10, whereinthe executable instructions, when executed by the processor, furthercause the apparatus to: determine the PUCCH resource in the determinedPUCCH area according to a mapping rule, wherein the mapping rule is aprinciple of selecting a PUCCH resource for transmitting ACK/NACKinformation in a PUCCH resource area.
 15. The apparatus according toclaim 14, wherein the first PUCCH resource area and the second PUCCHresource area correspond to different mapping rules.
 16. The methodaccording to claim 15, wherein one mapping rule in the different mappingrules is that the PUCCH resource is indicated by a start offsetinformation combined with a sequence number of a control channel element(CCE).
 17. A method, comprising: transmitting, by a base station to aterminal device, a physical downlink shared channel (PDSCH) on adownlink carrier of at least two downlink carriers, wherein the at leasttwo downlink carriers are capable of being configured for the terminaldevice; determining, by the base station, a physical uplink controlchannel (PUCCH) resource for carrying acknowledgement ornon-acknowledgement (ACK/NACK) in response to the PDSCH, wherein thePUCCH resource is dynamically located within a first PUCCH resource areaor a second PUCCH resource area; and receiving, by the base station onthe PUCCH resource, the ACK/NACK.
 18. The method according to claim 17,further comprising: transmitting, by the base station, an indicationindicating a PUCCH resource area in the first PUCCH resource area or thesecond PUCCH resource area.
 19. The method according to claim 17,wherein the first PUCCH resource area is for feeding back ACK/NACK in alegacy system, and the second PUCCH resource area is for feeding backconfirmation information in a system compatible with the legacy system.20. An apparatus, comprising: a storage medium including executableinstructions; and a processor, wherein the executable instructions, whenexecuted by the processor, cause the apparatus to: transmit a physicaldownlink shared channel (PDSCH) on a downlink carrier of at least twodownlink carriers, wherein the at least two downlink carriers arecapable of being configured for a terminal device; determine a physicaluplink control channel (PUCCH) resource for carrying acknowledgement ornon-acknowledgement (ACK/NACK) in response to the PDSCH, wherein thePUCCH resource is dynamically located within a first PUCCH resource areaor a second PUCCH resource area; and receive, on the PUCCH resource, theACK/NACK.
 21. The apparatus according to claim 20, wherein theexecutable instructions, when executed by the processor, further causethe apparatus to: transmit an indication indicating a PUCCH resourcearea in the first PUCCH resource area or the second PUCCH resource area.22. The apparatus according to claim 20, wherein the first PUCCHresource area is for feeding back ACK/NACK in a legacy system, and thesecond PUCCH resource area is for feeding back confirmation informationin a system compatible with the legacy system.